video mixing??

Hi,

I want to mix several live digital camcorder feeds and this mixed feed then recorded in lossless compression ie. mpeg1/mpeg2 and also streamed simultaneously onto the web. The streaming onto the web will not take place every time othertimes the mixed feed will be required for event big screen usage etc.

I understand that this can be done in 2 ways either by using hardware or software pc based vision mixer..

Any recommendations on wether to use software or hardware based mixers and which ones in particular.

The feeds from the cameras will be of live interviews/events from different angles.

Current Hardware:
1x pc high Intel duocore with loads of ram and sata harddisc space
2x Canon hx30 camcorder w/tripods
1x sony HVR-z1 w/tripod

I dont have thousands of pounds to spend, as working from home and a very tight budget...so any advice on this would be most helpful.

thanks in advance.

Nathan.R